Various apparatus for exercising the jaw and facial muscles have been known in the art for many years. Typically, these exercisers utilize springs and tension bars to bias various components or have handles and appendages for moving the device in the mouth. For example, U.S. Pat. No. 3,547,433 to Robins discloses a slightly flexible noncompressible arcuate member which is inserted between a lip and underlying gum area for strengthening the facial muscles by selective tensioning and relaxing of the lip over a bulge created in the member. U.S. Pat. No. 4,185,817 to Peterson discloses a teeth exerciser with a U-shaped configuration formed of a yieldable resilient material providing a plate surface for the teeth being exercised. U.S. Pat. No. 4,196,902 to Borriello discloses a crescent shaped piece of resilient material which is inserted between the upper and lower teeth to exercise the facial muscles by overcoming the resistance of the material. Finally, U.S. Pat. No. 4,280,696 to Ramon discloses an exerciser apparatus having a pair of flat spring arms pivotally connected to each other by 360.degree. convolutions of a torque spring. The mouth is exercised by biting on the jaws which are biased away from one another.
While all of the above-described prior art devices provide apparatus for exercising the facial muscles, they have several drawbacks. First, devices which are inserted between the teeth and gum are awkward to manipulate, and do not provide protection against the grinding of the teeth. Mechanical apparatus inserted between the upper and lower teeth are relatively cumbersome to manipulate, and can pinch or catch portions of the mouth during operation. Many prior art devices fill the space between the upper and lower teeth, like mouthguards and the like, but prevent free breathing of the user during the exercise.
In addition, the inventor herein has found that "resistance exercise" is helpful with respect to the oral muscles, if the jaw is properly positioned in its socket. Without this proper positioning, as a person uses or exercises a muscle or muscle group, the muscle is actually losing its strength rather than increasing in strength.